From the eighteen cases, twelve of chondromalacia and six of hypertrophy of the patella, we may conclude that:
1. More attention should be given by orthopaedic surgeons to the pateila in mechanical difficulties of the knee.
2. The patella is an essential part of the knee joint, and should not he removed indiscriminately.
3. There are few indications for removing the patella completely, chief of which is a badly comminuted fracture.
4. Articular changes in the patella may follow acute or recurrent trauma, or may be part of the general aging process of the knee joint.
5. If operation for chondromalacia of the patella becomes necessary, a conservative procedure, such as resection of the disintegrating articular cartilage, is indicated. Patellaplasty may be indicated in the severe case.
6. For the hypertrophic patella which is causing discomfort, patellaplasty, with removal of loose bodies and the menisci, is sufficient to give the best operative result.
7. With every knee arthrotomy, the patella must be examined by palpation or by direct vision.